Carb for Nelson
12-03-2007, 04:40 PM
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Carb for Nelson
I have seen some post that there was a carb that would fit a nelson Q40. Anyone know what it was? I tried sending an email to psp and called a couple times, phone busy and they have not answered my email. Appreciate any help. I realize this engine wont throttle like a sport engine but I would like something between off and screaming.
12-04-2007, 06:42 AM
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RE: Carb for Nelson
I have experimented with the Perry Carb on my Nelsons. A very frustrating experience - despite the excellent service from Gary Conley at Conley Engines. My problem was that the plastic sleeve around the carby spigot keeps coming loose. I think the locking bar distorts the sleeve and loosens it. I've tried different glues without success.
Its frustrating because I've discovered that the Nelson idles very nicely on the Perry Carby and its so easy to practice on your own without a launcher.
Its frustrating because I've discovered that the Nelson idles very nicely on the Perry Carby and its so easy to practice on your own without a launcher.
12-04-2007, 08:51 AM
#6
RE: Carb for Nelson
My Nelson Q-500 has a Performance Specialties supplied Super Tigre carb. I should mention that there is some modification and machining to the bottom of the carb to fit the Nelson case. As other pointed out it idles very well.... but, it does hurt the top end performance considerably.
Bill Vail
Bill Vail
12-04-2007, 09:50 AM
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RE: Carb for Nelson
I know you asked about the Nelson, but if you want a solution that will work well, JETT has an engine that works well. This is my post from the NMPRA forum.
I have a Quickie JETT with a RED JETT carb on it that I used to test fly Quickies with. I never really checked it out performance wise because I was just using it for test flying. I'm thinking about putting it on a sport plane and I wanted to get some numbers. I had a about an hour of daylight left this afternoon and I decided to put it on the test stand.
So I put an APC 8.75x8.0NN prop on it and mounted it on the test stand. I stuck a remote needle valve on it so I wouldn't have to get near the prop.
After a little adjusting, I got it to idle at about 3500 rpms and about 19,500 on the top end. I think that with a servo controlling the throttle, it will idle around 3000. I seem to remember it idling a little slower on the planes.
It does take a little work to get it to transition properly. If everything is not pretty close to where it needs to be, it will die as it comes on the pipe.
But for all those guys out there that want an engine that will idle and work well for sport flying, this engine is a great choice. It seems to have more power than a Sport JETT .50, but the .50 will swing bigger props.
Now I just have to decide which plane I'm going to put it on. I wonder if a Sky Raider Mach II can handle about 30 more mph.
So I put an APC 8.75x8.0NN prop on it and mounted it on the test stand. I stuck a remote needle valve on it so I wouldn't have to get near the prop.
After a little adjusting, I got it to idle at about 3500 rpms and about 19,500 on the top end. I think that with a servo controlling the throttle, it will idle around 3000. I seem to remember it idling a little slower on the planes.
It does take a little work to get it to transition properly. If everything is not pretty close to where it needs to be, it will die as it comes on the pipe.
But for all those guys out there that want an engine that will idle and work well for sport flying, this engine is a great choice. It seems to have more power than a Sport JETT .50, but the .50 will swing bigger props.
Now I just have to decide which plane I'm going to put it on. I wonder if a Sky Raider Mach II can handle about 30 more mph.
12-04-2007, 10:45 AM
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RE: Carb for Nelson
One more thing. Dub Jett made mounts for the Thunder Tiger Pro 40 that allow swapping a TT Pro 40 and a Q-40 engine just by changing mounts. Some have been used in Q-40 Sport planes. Dub may still have some. If he doesn't, I do, and I think Kevin Matney does also.
I know that Duane Gall has done a Polecat for Q-40 Sport and reported good things. The top speed is in the 140 range, but you get to have a nice idle and speed range.
I know that Duane Gall has done a Polecat for Q-40 Sport and reported good things. The top speed is in the 140 range, but you get to have a nice idle and speed range.
12-09-2007, 10:49 PM
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RE: Carb for Nelson
Thanks guys I found a carb that will work with some machining. Don, I appreciate the suggestions but I have a Jett in a q500 and I already have the nelsons.
12-18-2007, 11:37 PM
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RE: Carb for Nelson
For anyone interested heres what she looks like, runs great, good transition and idle. Midrange sucks, leans out but I got what I am looking for, ability to throttle back and pull the underwear out of my pucker. Only venturi type plane I have flown was an 049 pylon that we would run solid lines in the fuel tank so you had to roll inverted to shut off the engine. Just a little nervous test flying a q40 without some kind of throttle. Thanks for putting up with the questions.
12-19-2007, 12:04 AM
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RE: Carb for Nelson
Eco,
Your carby looks just like the Perry I've been experimenting with. My motivation was to get a set up where I could practice on my own without having to launch on full throttle with only one hand on the Tx.
How many flights have you had with the Perry Carb so far?
Does yours have a plastic sleeve around the spigot that matches the hole in the Nelson crankcase?
Mine does and the plastic sleeve keeps coming loose.
Your carby looks just like the Perry I've been experimenting with. My motivation was to get a set up where I could practice on my own without having to launch on full throttle with only one hand on the Tx.
How many flights have you had with the Perry Carb so far?
Does yours have a plastic sleeve around the spigot that matches the hole in the Nelson crankcase?
Mine does and the plastic sleeve keeps coming loose.
12-19-2007, 10:56 AM
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RE: Carb for Nelson
Joe
Thats precisely why I wanted a carb as well.
Havent flown it yet just run it on the test stand.
No sleeve I used the perry carb for the G2300, had to turn down the od about .030 and shorten it a bit I also used a carb retaining bolt where the stock needle valve was.
Try using some high temp silicone to keep the carb together, I use the stuff for all kinds of things and it never comes loose.
Thats precisely why I wanted a carb as well.
Havent flown it yet just run it on the test stand.
No sleeve I used the perry carb for the G2300, had to turn down the od about .030 and shorten it a bit I also used a carb retaining bolt where the stock needle valve was.
Try using some high temp silicone to keep the carb together, I use the stuff for all kinds of things and it never comes loose.
01-05-2008, 09:19 AM
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RE: Carb for Nelson
The problem is not the aluminum spigot turning in the crankcase. The problem is the plastic spigot of the Perry carby turning inside the aluminum sleeve around the spigot. I've tried JB Weld etc without success. I suspect the answer is a material other than Aluminum that does not expand so much when hot.
